Sanitary check valve



FIG. 1 is a bottom front perspective view of a sanitary check valve, showing my new design;

FIG. 2 is a top front perspective view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is an elevational view thereof; and,

FIG. 5 is a bottom view thereof. 

The ornamental design for a sanitary check valve, as shown and described. 